I went shooting with the about $1699 Sony 12-24mm f/4G tonight, only to discover to my utter frustration as it grew dark that the series and comparisons I just shot had been done with IBIS enabled, which renders the results useless (damage was visible with a clear loss of sharpness).

The idea that IBIS has any use at all with multi-second exposures is dubious at best. I wish I could program the A7R II with a “Never use IBIS below 1/__ second".

Well, the night’s shoot is ruined—I will have to go reshoot. What a bummer since that delays things a day.

Peter H writes:

I always thought that the reason IBIS degraded image sharpness on a tripod was because the IBIS system tried to (unsuccessfully) compensate for the vibration caused by the first shutter curtain; so, wouldn't using electronic first curtain mitigate this? I must be wrong about this as I presume you always shoot in electronic first curtain mode?

DIGLLOYD: with Sony, I always hoot with electronic first curtain shutter. That is, there is a mechanical closing curtain.

Gear menu #5 => 3-Front Curtain Shut.

Logic is a good starting point but logic rests on premises, that can be false (and sometimes I don’t know what I don’t know), so there is no substitute for verification—give it a shot. What I do know is that IBIS causes problems particularly for longer exposures, and thus the logic that IBIS should have no effect for the EFC shutter is incorrect.